DE 199 62 988 A1 discloses a vehicle door with a door box including a first wall and a second wall. A window frame module is inserted into a gap on the upper side of the door box and anchored therein during the assembly of the door box. An inner window shaft reinforcement is installed in the door box beforehand for stabilizing the door box for this purpose. However, if the door box lacks stability without the window shaft reinforcement, the problems to be prevented with the stabilization during the installation of the window frame module consequently would also interfere with the installation of the stabilizing component such that the problem of lacking stability ultimately is only shifted, but not solved.
Accordingly, there is a need in the art to develop a vehicle door that can be easily and cost-efficiently assembled.